1. Field of the Invention
The invention relates to the field of thermal insulation systems and, in particular, to a thermal insulation system for use on high speed aircraft or spacecraft.
2. Description of Related Art
High speed aircraft, (Mach 4 and above) and spacecraft, like the space shuttle, which is subjected to extreme heat and aerodynamic loads upon re-entry into the atmosphere, require thermal protection systems. The space shuttle uses a heat resistant nose cone and special treatments on the leading edges of the airfoils. Typically, this material comprises a carbon matrix reinforced with carbon fibers. However, ceramic tiles are used elsewhere along with thermal blankets as disclosed in U.S. Pat. No. 4,151,800 Thermal Insulation Protection Means by R. I. Dottz, et al. and coated Nomax® depending upon the severity of heating. The ceramic tiles or bricks are bonded to the aluminum fuselage with gap filler material there between. While these tiles have worked successfully, on future vehicles, stronger and more damage resistant tiles are desirable.
U.S. Pat. No. 5,741,574 Truss Reinforced Foam Sandwich and U.S. Pat. No. 5,624,622 Method Of Forming A Truss Reinforced Foam Sandwich Construction both by J. S. Boyce, et al. disclose a foam core sandwiched between face sheets. The foam core is reinforced with tow members extending there through and retained by the adhesive bonding the face sheets to the core. While the concept of reinforcing the foam core is useful, the sandwich construction is not suitable for use as a replacement tile on vehicles such as the space shuttle or future versions thereof. What is needed is an improved tile that is stronger, but light in weight and provides increased resistance to aerodynamic abrasion.
Thus it is a primary object of the invention to provide an improved tile for use on high speed aircraft or spacecraft that is structurally stronger than existing tiles.
It is another primary object of the invention to provide an improved tile for use on high speed aircraft or spacecraft that is structurally stronger than existing tiles and is still light in weight.
It is a further object of the invention to provide an improved tile for use on high speed aircraft or spacecraft that is structurally stronger than existing tiles, light in weight, and provides increased resistance to abrasion.